remove /citation feature

probably just revert this commit later and make some changes to this
feature when it’s ready to be working
prefix API calls with a specific version number
reduce #page parameters count and extract logic
make #page return one level nesting hash
remove useless key/value from #page hash
extract pagination logic to #pagination(works)
make facets sidebar work
hash alignment
params is already included
remove unused method
add facet filters
"Other IDs" is useless
it works after adding facet filters